Intel Core 2 Duo vs Intel Core 2 Quad?

Depends upon what the computer is used for as to whether a Duo or Quad provides the most value, but higher clockspeed is always better. Get the 2.66Ghz one.

Since Core 2 Quads are more expensive, you can often get a FASTER Core 2 Duo for the same price.

For example, the 3.0Ghz Core 2 Duo E8400 and 2.4Ghz Core 2 Quad Q6600 cost about the same. For gaming, the higher-clockspeed E8400 performs better. For multitasking, movie editing and 3d design programs the Q6600 is better.

If the CPUS you're comparing have the same speed rating and you don't mind spending more, get the Quad. But never buy a slower quad for gaming. The CPU clockspeed is more important than whether it's duo or quad.

The people who think multiplying clockspeed by the number of cores is how you calculate processor speed have no clue- ignore them, it does NOT work that way.

**Update**

The Q6700 is better than the Q6600 - it's 2.6Ghz instead of 2.4Ghz.

Let me second what C-Man said. For pretty much every game and application out now, and for the vast majority of games and applications over at least the next two years, having a dual-core versus a quad-core will make almost no difference in typical applications. However, having a faster CPU will make a huge difference.

3GB versus 4GB will make almost no difference, especially if you install a 32-bit operating system.

In the case you gave, the quad-core is better in all respects. Four cores are not going to ever be worse than two. And 2.66GHz is always going to be better than 2.0GHz (unless the dual-core is from a much newer line, but that's doubtful, and Intel's oldest quad cores - Kentsfield - are not different enough from the newest dual cores - Wolfdale - to outweigh the clock speed difference).

Update: The Q6700 runs at 2.66GHz, so that will make the quad core a faster CPU than the dual core at the same speed. However, it won't make all that much difference for two reasons. First, most software available today and for the next few years can't take advantage of more than two cores very well. Second, those four cores are sharing the same FSB and memory, and that will start to be the limiting factor.

The Core 2 Quad will definitely perform better. It is able to run 4 processes simultaneously, each on a different core, and this definitely minimizes lag. As for applications these days, more and more are being written to utilize a 4 core processor, so the core 2 quad, which I believe is the Q6600 that you're talking about, is a great buy. I have one on one of my builds and it runs superbly and I almost never see any lag, even while gaming.

The Intel Core 2 Duo has a set of two processors, with a speed of 2 Ghz. This would total processing of 4.0Ghz.

The Intel Core 2 Quad has a set of two processors, with a speed of 2.66Ghz. That would total 10.64Ghz.

The more the total, the better the processing power.

RAM is virtual memory. The more virtual memory your computer has, the more software it can handle at a single time. So: 4GB RAM would be better than 3GB RAM.

You should get the Intel Core 2 Quad (2.66Ghz) with 4GB RAM for maximum performance.

The Quad core one is better. More RAM and the processor is faster. If those are the two choices go with the Quad core one.

The core 2 quad is better and faster and more reliable by quite a bit, allthough the core 2 duo is also a good reliable processor, but quad is definitley better

the intel Core 2 Quad processor is better.

Intel Core 2 Quad with 2.66Ghz is best!

Obviously the Core 2 Quad, it has a higher clock speed, double the amount of cores and the system has more RAM.

core 2 quad is better